Band knife sharpening means



July 15, 1958 2. KLIKA BAND KNIFE SHARPENING MEANS 2 Sheets-Sheet 1 Filed Nov. 23. 1956 v INVENTOR. v Zdenek SY/M n dfy/f July 15, 1958 z, LIKA 2,842,907

BAND KNIFE SHARPENING MEANS Filed NOV. 23, 1956 2 Sheets-Sheet 2 INVENTOR.

BY ww s/ BAND KNIFE SHARPENING MEANS Zdenk Klika, Prague, Czechoslovakia, assignor to Pragodv, vyroba dmsk a dtsk konfekce, narodnl podnik, Prague, Czechoslovakia Application November 23, 1956, Serial No. 624,140

2 Claims. (Cl. 51-247) The present invention relates to a band knife cutting machine having knife grinding or sharpening means; The Working space around the knife grinding or sharpening means in such a machine has hitherto not been protected against the accumulation of grinding dust penetrating into the operators lungs, soiling the cut material, and increasing the wear of the knife guides.

The above disadvantages are avoided in accordance with the invention by providing in the vicinity of the place where the band knife is ground, a hood with an assembly of resiliently mounted seals adjacent slots formed in the hood for the passage of the knife.

An illustrative embodiment of the invention is shown in the accompanying drawings.

Fig. l is an elevational view of a hood device embodying the invention,

Fig. 2 is a sectional view along the line II-II of Fig. 1,

Fig. 3 shows diagrammatically the arrangement of the hood device on the machine,

Fig. 4 is a perspective view of a sealing assembly included in the hood device,

Fig. 5 shows a sealing member in an elevational view,

Fig. 6 is a plan view of the sealing member, and

Fig. 7 is a sectional view along the line VII-VII of Fig. 5.

A hood 1 (Fig. 3) embodying this invention includes a dish-shaped base plate 2 (Fig. 2) provided with slots 3 for the passage of a band knife 4, which is to be ground by means of suitably driven grinding wheels 5. Mounted on the base plate 2 are guides 6, on which a transparent portion of the hood is mounted by means of hollow guiding members 7. The transparent portion of the hood 1 consists of a transparent sleeve 8 secured in grooves of rings 9, 10 by means of screws (not shown) and further of a transparent lid 11, secured, for example, by screws (not shown) to the front ring 10. The hollow guiding members 7 are fastened to the rings 9, 10. The t ansparent portion of the hood 1 is tightened nited States Patent 2,842,907 Patented July 15, 1953 ice against the base 2 with a rubber seal 12, mounted in the rear ring 9, therebetween by means of two locks 13 (Fig. 1, Fig. 2) pivotally carried by the ring 10 and having helical surfaces 14 engaging corresponding slots in the guides 6. The locks 13 serve also as handles for removing the transparent portion of the hood 1.

The seal for the band 4 comprises an assembly of hollow, generally cylindrical sealing members 15 provided with a rectangular gap 16 (Figs. 6, 7) which is slightly wider than the thickness of the knife 4. The seal adjacent the outlet or lower slot 3 comprises a plurality (three in the illustrated embodiment) of sealing members 15 placed in a holder 17 (Fig. 4) secured to the base plate 2 of the hood 1. The inlet seal adjacent the upper slot 3 comprises only one sealing member 15 in a holder 18 (Fig. 2) which also carries a guiding roller 19. The sealing member 15 may be formed of metal, or any other suitably hard, wear resistant material.

Both ends 15a of each sealing member 15 are flat and received in rubber inlays 20 provided in slots of the holders 17, 18. The inlays 20 allow the sealing members 15 to rock about their longitudinal axes and to slide in horizontal direction, under the influence of deformations of the knife 4. The wiped off grinding powder falls to the interior of the hood through lateral slits 21 which extend from the interior cavity of each hollow sealing member 15 to the external surface of the latter.

I claim:

1. In a cutting machine having a band knife and grinding means engageable with the knife for sharpening the latter; the combination of a hood extending around said grinding means and having slots for the passage of the knife therethrough, and a sealing assembly within said hood adjacent each of said slots, each sealing assembly including at least one generally cylindrical hollow sealing member having a diametrical slit extending therethrough and loosely receiving the band knife, the ends of said sealing member being flattened, a holder and resilient inlays in said holder engaging said flattened ends of each sealing member to permit rocking of the latter about its longitudinal axis as well as transverse displacement of the sealing member relative to said holder.

2. In a cutting machine having a band knife and grinding means engageable with the knife for sharpening the latter; the combination as in claim 1, wherein each sealing member further has passages opening from the hollow interior thereof to the external surface at opposite sides of said diametrical slit for removal of grinding dust through said passages.

References Cited in the file of this patent UNITED STATES PATENTS 2,786,314 Simmons Mar. 26, 1957 

